JPH0285708A - Angle detector for press work - Google Patents

Abstract

PURPOSE:To make the press angle of a work coincident with a sample angle by providing a base, a lens, and a filter. CONSTITUTION:A base 10 is arranged so that a lens 26 can face the press end face of a work put between a pressurizing table and receiving table. Screens 66 and 68 are faced to sensors 74 and 76 by turning a lever 62. Then, after the magnification of images projected on the screens 66 and 68 is set to a desired one by loosening a screw 160 and sliding a lens in the length direction, the lens 20 is fixed to a cylindrical body 18 by tightening the screw 160. After the lens 20 is fixed, the images of the work projected on the screens 66 and 68 are brought into focus by rotating the holder of a lens 26. In case the work is made of the same material as that of the pressurizing and receiving tables and the end face of the work is in the same degree as those of the tables, the end face of the work is painted to red in accordance with a green filter 34. Therefore, the contrast between the end face of the work and the other sections can be made larger and the end face of the work can be distinguished from the other sections.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention optically projects the end face of a V-shaped bent portion of a target workpiece, and arranges a photoelectric sensor for photoelectric detection on the image plane to determine the press angle of the target workpiece. The present invention relates to an angle detection device for press work that measures the angle of the press work.

When using a press brake receiver, a workpiece 4 made of a metal plate is placed on a mold on a table 2, and the workpiece 4 is pressurized by a pressure table to set the angle of the workpiece 4 as shown in FIG.
The angle of the workpiece 4 changes slightly depending on the pressure of the pressure table 6. In the press brake, once the workpiece 4 is removed from the support stand 2, it cannot be pressed again.

In addition, the workpiece 4 located between the stand 2 and the pressure table 6 is placed on the stand 2.
The angle cannot be measured with a measuring device because of the angle 6 degrees. Therefore, conventionally, after pressing the workpiece 4, it was removed from the stands 2 and 6, and the pressing angle of the workpiece was measured using a separately provided measuring tool.

When the angle is larger than a predetermined value, the pressure table 6. The pressure on the workpiece 4 is readjusted in the direction of increasing it.

In this case, until the workpiece 4 is set at a predetermined angle.

Many defective products are produced. SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide an angle detection device that can detect the angle of the press work without removing it from between the press table and the support table.

The configuration of the present invention will be described in detail below based on embodiments shown in the accompanying drawings.

In FIGS. 2 to 4, reference numeral 10 denotes a base, on which a mounting plate 12 is erected.

An arm is fixed to the base 10, and a lighting fixture 1 is attached to the arm.
4 is attached so that the angle can be adjusted. The mounting plate 12
A tubular holder 16 is fixed to the holder 16, and a cylinder 18 is rotatably fitted into the holder 16. The cylinder 18 is fixed to the holder 16 with screws. An internal cylinder 2o is slidably fitted into the cylinder 18, and a casing 22 is fixed to the front end of the cylinder 20. Casing 22
A guide 24 is fitted and fixed in the opening of the guide 24.
A threaded portion formed on the outer diameter of the holder that holds the lens 26 is screwed into a threaded portion formed on the inner diameter of the holder.

Reference numeral 28 denotes a screw fixed to the guide 24, on which a bevel gear 30 is rotatably supported, a filter holder 32 is fixed to the bevel gear 30, and colored filters 34 and 36 are vertically disposed on this screw. . Filter 34 is colored green, and filter 36 is colored red. , 38
is a shaft rotatably supported by the mounting plate 12, a rope pulley 40 is fixed to one end of the shaft, and a pipe 4 is fixed to the other end.
2 is fixed. Reference numeral 44 denotes a cylindrical body that is slidably fitted onto the inner circumferential surface of the pipe 42. One end of a shaft 46 is fixed to this cylindrical body, and the other end of the shaft 46 is rotatably supported by the casing 22. A long groove is formed in the pipe 42 along its longitudinal direction, and a pin fixed to the cylindrical body 44 is slidably arranged in the long groove. The middle portion of the shaft body 46 is connected to the casing 22. It is rotatably supported by a bracket 48 fixed to. A bevel gear 50 is fixed to the shaft body 46, and the bevel gear 5o meshes with the bevel gear 30. 52 is the mounting plate 12
This is a pulse motor fixed to the output shaft of the pulse motor, and an endless rope is passed between the rope pulley fixed to the output shaft of the pulse motor and the rope pulley 40. 54 is a holder fixed to the internal cylinder 20, and a heat insulating filter 56 is fixed to this. 58 is a tube rotatably supported on the mounting plate 12, on which a shaft 60 is rotatably arranged, a lever 62 is fixed to one end of the shaft 60, and a member 64 is fixed to the other end. A screen 66 made of a glass plate for checking focus is fixed to the zero member 64 to which is fixed. A lever 67 is fixed to one end of the tubular body 58, and a glass screen 6 for checking the focus is attached to the other end via a member.
8 is fixed. Reference numerals 70 and 72 are sensor holding members, the upper end of which is rotatably attached to the mounting plate 12 with shafts 74a and 76.
a It is supported. Photoelectric sensors 74, 76, 78, 80 are attached to the sensor holding members 70, 72. As the photoelectric sensors 74, 76, 78, 80, commercially available line sensors are used in this embodiment. The line sensor has a large number of minute light detection elements arranged in a straight line.

The sensor is located within a through hole formed in the mounting plate 12. At the bottom of the sensor holding member 70, 72,
Holes 82,84 are provided through the shaft 74 of the holes 82,84.
Index holes 86, which are stepped screw holes, are transparently provided in the mounting plate 12 at a predetermined pitch, positioned on a line of rotation centered on a and 76a. Adjacent to the holes 82.84, the retaining members 70.72 have fine adjustment of the angle of the members.

Holes 88 and 90 for this purpose are located on the alignment line of the index holes 82 and are transparent therein. 92 and 94 are limit switches having a stopper function, and are attached to the casing 22.

The limit switches 92 and 94 are connected to a controller (not shown) that drives the pulse motor 52.

FIG. 6 shows the central processing unit CPU of this device, 100 is a P/L/X oscillator, 102, 104, 106°, and 108 are timing control circuits, which generate timing for driving the photoelectric sensor. 110.112,114,
A driver 116 converts the timing signal generated by the timing control circuit into a level that can drive the sensor. Amplifier circuits 118, 120, 122, and 124 differentially amplify the output signals from the photoelectric sensors 74, 76, 78, and 80. 126, 128, 130, 132
is a slice level setting circuit that slices an analog signal at a fixed level and converts it into a digital signal. 1
34 is a counter control circuit, and oscillator 10
The signal from sensor 74.76.78.80 is compared with the signal from sensor 74.76.78.80 to determine the range to be counted. 136 is a counter circuit, counter control circuit 1
The pulses output from 34 are counted. 138 is an arithmetic circuit, which calculates the center of the thickness of the workpiece 4 based on the numerical value counted by the counter circuit 136;
The correction value in the angle setting input circuit 142 is calculated to determine the distance of the center from the coordinate reference. 14
0 is a register circuit, which stores four types of values obtained by the circuit 138 described above. A calculation circuit 146 calculates the angle A of the workpiece 4 based on the sensor interval value from the register circuit 140. Reference numeral 150 denotes an angle setting input circuit 2142, which sets the approximate angle of the workpiece 4 and stores correction values at each angle.

Next, the operation of this embodiment will be explained.

First, the base 10 is arranged so that the lens 26 faces the press end surface of the workpiece 4 held between the pressure table 6 of the press brake and the press plate 2 . Next, rotate the lever 67.62 to connect the screen 66.68 to the sensors 74, 76.7.
8. Place it opposite to 80. Next, loosen the screw 160 and
Slide the internal cylinder 20 in its longitudinal direction, set the image reflected on the screen 66°68 to the desired magnification, and then tighten the screw 16.
0 to fix the internal cylinder 20 to the cylinder 18. Next, rotate the holder of the lens 26 to remove the screen 66.
Focus the image of work 4 reflected in 68. When the pressure table 6 and the press brake stand 2 and the workpiece 4 are made of the same material and have the same end surface condition, the end surface of the workpiece 4 is painted red in accordance with the green filter 34. Thereby, the contrast between the end face of the workpiece and other parts can be increased, and the end face of the workpiece and the tables 2 and 6 can be distinguished. If the end surfaces of the tables 2 and 6 and the workpiece 4 are different, the optical images of the tables 2 and 6 and the optical image of the workpiece 4 can be distinguished using a central processing bag [colored filter 34. Or, it is not necessary to provide the motor 5.
By driving the bevel gear 50.30 and rotating the bevel gear 50.30, the red filter 36 can be positioned on the optical image of the workpiece. When using the red filter 36,
The end face of the workpiece is colored green. Sensors 74, 7 on a predetermined optical image of the work 4 depending on the pressing angle of the work 4
6. Determine the angle of rotation of the retaining member 70.72 about the axes 74a, 76a in order to position the stepped screws 162 through the holes 82° 84 or 88.90 to the desired index. Screw the holding member 70 into the hole 86.
．． 72 is fixed to the mounting plate 12. After setting the fixed angle of the holding member 70 , 72 , the angle value is input into the circuit 142 . This angle value can be configured to be automatically input to the circuit 142 by a signal such as a switch provided for each index hole.
Based on this angle value, an XS coordinate correction value, which will be described later, is created. The workpiece 4 is irradiated by the proving device 14, and the optical image of the workpiece 4 is irradiated onto the photoelectric sensors 74, 76, 78, and 80. At this time, the screens 66 and 68 are connected to the lever 62,
The measurement switch 16 is rotated to move it above the front proximity position of the sensors 74, 76, 78, 80.
When 4 is pressed, the detection signals of each sensor 74, 76, 78, 80 are input to the counter control circuit 134. The signal from sensor 74 will now be explained. The signal of sensor 74 is converted by circuit 126 into a digital signal as shown in FIG. 9C. A low-level portion C of the digital signal in FIG.
While counting the distance between
Count the distance C between T and XR by the number of pulses. This count value C is input to the calculation circuit 138, where b+(c/2)=d is calculated. The calculation circuit 138 calculates the X coordinate value x1 of the center point P1 of the optical image of the workpiece 4 based on the d value and the X coordinate value of Xs based on the angle correction value of the circuit 142. By the same operation as above, the arithmetic circuit 138 calculates P2. P3. The X coordinate value of point P4 is calculated and these values are stored in register 140. The arithmetic circuit 146 includes the above X1, x2 and the sensor 74.
．． 76 distance! Based on, X=1x21 lxl, l
First, calculate 5inC1=X/J2, and then calculate C1=Sin''X/4.

YPJ using the same yK principle as above! P3 for the reference axis. P4
Calculate the angle C2 of the line segment passing through. The angle A of the workpiece 4, which is the sum of C1 and C2, is digitally displayed on the display 150. The operator presses the pressure table 6 while looking at the above display.
Increase the pressing force until the workpiece 4 reaches a predetermined angle,
A desired pressurizing force of the pressurizing table 6 can be obtained. This pressing force, ie, the amount of approach of the pressurizing table 6 to the table 2, is stored in a storage device. In addition, when measuring the angle of work 4,
The pressure table 6 is moved slightly away from the table 2 to release the pressure on the workpiece 4. This is because the workpiece 4 has a tendency to return to its angle slightly when the pressure from the pressure table 6 is released, and this return needs to be taken into consideration. As shown in FIG. 8, a half mirror H is placed between the sensor D and the lens L, a screen S is placed above the half mirror H, and the midpoint between the half mirror H and the sensor 0 If the distance a and the distance between the screen S and the midpoint of the half mirror H are set to be the same, the image on the sensor D can be viewed with the screen S, which is sold separately. In the figure, F
is a colored filter and G is an adiabatic filter. still,
In this embodiment, as shown in FIG.
A semi-fixed method using four wires at 4, 76, 78, and 80 degrees is adopted, but the method is not particularly limited to this method.

For example, as shown in FIG.
An image parallel scanning method using this method may also be adopted.

In this method, the angle of the workpiece is measured by moving one sensor 170 on the left and right sides up and down. By arranging the sensor 170 diagonally and moving at a pitch of about 173 of the sensor length, the entire area of the pressed part of the optical image of the workpiece can be covered. Also, FIG. 12 shows the line sensor 172. ．． This shows an image parallel scanning method using one line. FIG. 13 shows an image rotation scanning method using one line sensor 174. If the sensor 172 is tilted to use a rotational scanning method, it can be rotated at a pitch of 15 to 18 degrees to cover the entire press area of the workpiece light image. FIG. 14 shows an image rotation scanning method using 176.2 single-element sensors. This method is a single element version of the method shown in Fig. 13 above, and requires a fine scan pitch, but since the reading time for a single element is short, the overall fixed time is also more advantageous than the method shown in Fig. 12 above. Become. FIG. 15 shows a semi-fixed system using 178.4 to 8 single-element sensors.

Although the method shown in Fig. 10 is made into a single element, the workpiece light image 1
Since it is not possible to cover the entire area of 80, this is the cheapest method in which manual settings are made each time according to a regular sample depending on the target work. With this method, it is only possible to detect whether or not the press angle of the workpiece matches the sample angle, so the operator must apply pressure while watching the display on the 1 display until the workpiece angle matches the sample angle. Place the stand close to the stand.

The present invention has the advantage of being able to detect whether the workpiece angle matches the sample angle with a simple structure using a single element sensor, and thereby allowing the press brake to be operated to make the press angle of the workpiece match the sample angle. exists.

[Brief explanation of the drawing]

Figure 1 is an explanatory diagram of the press brake, Figure 2 is a plan view, Figure 3 is a sectional view taken along line A-A, Figure 4 is a rear view, Figure 5 is a schematic diagram, and Figure 6 is a block circuit diagram. , Fig. 7 is an explanatory drawing, Fig. 8 is an explanatory drawing, Fig. 9 is an explanatory drawing, Fig. 10 is an explanatory drawing, Fig. 11 is an explanatory drawing, Fig. 12 is an explanatory drawing, Fig. 13 is an explanatory drawing, FIG. 14 is an explanatory diagram, and FIG. 15 is an explanatory diagram. 2...Receiver is stand, 4...Workpiece, 6...Pressure stand, 1
o...Base, 12...Mounting plate, 14...Lighting device, 16...Holding body, 18...Cylinder body, 20...Lens, 34.36...Filter, 66 ...Screen, 68...Screen, 70.72...Sensor holding member, 74,76.78,8o...Photoelectric sensor,
86... Index hole. Patent Applicant Muto Kogyo Co., Ltd. Representative Patent Attorney Aya Nishijima Figure 1 Figure 5 Figure 7 Figure 8 Figure 12 Figure 13 Figure 14 Figure 15 Procedural Amendment Statement September 2, 1989 - Violence 7°)! to

Claims (1)

[Claims] 1. Base 10 and lighting fixture 14 attached to base 10
, a lens 20 attached to the base 10, and the lens 2
A single-element sensor 178 is located behind the lens 20 and is arranged in accordance with the sample angle of the workpiece, facing the workpiece light image entering the lens 20. When the light image of the workpiece coincides with the sensor 178, the An angle detection device for press work comprising a processing device that generates a coincidence signal based on the output of a sensor 178, and a display device that displays the coincidence signal.